Subtract 42/40 from 21/36
1st number: 21/36, 2nd number: 1 2/40
21/36 - 42/40 is -7/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 36 and 40 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 36 × 10 = 360,
21/36 = 21 × 10/36 × 10 = 210/360 - Likewise, for the 2nd fraction, since 40 × 9 = 360,
42/40 = 42 × 9/40 × 9 = 378/360 - Subtract the two like fractions:
210/360 - 378/360 = 210 - 378/360 = -168/360 - After reducing the fraction, the answer is -7/15
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